TCP connections hanging in FIN_WAIT_1

[Scott Bennett]

     I'm running FreeBSD 6.3-STABLE, compiled with updates as of 13 Aug. 2008,
and I'm seeing TCP connections that have been in FIN_WAIT_1 state for at least
eleven *hours*.  It has been years since I last read all the specs on TCP
close processing, but my recollection is that the entire sequence was limited
to only two or three minutes.  I couldn't find a bug report, but that proves
nothing.  Does anyone know of such a bug?  Or some weird condition I should
look for that might cause TCP connections to get stuck in the closing sequence
somehow?
     The hardware configuration is a Dell Inspiron XPS with a Broadcom BCM5705
A1 adaptor, ASIC rev. 0x3001, (bge driver) for 10/100/1000 Mb/s connected to a
Comcast/RCA cable modem at 100 Mb/s.
     Thanks in advance for any information you may have.


                                  Scott Bennett, Comm. ASMELG, CFIAG
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